Let-off device for looms



Sept. 8, 1931. c. HAKEMEYER LET-OFF DEVICE FOR LOOMS Filed March 2. 1929 FIG.3

INVENTOR CHARLES HAKE M EYER ATTORNEY Patented Sept. 8, 1931 PATENT OFFICE CHARLES HAKEMEYER, F PATERSON, NEW JERSEY LET-OFF DEVICE FOR LOOMS Application filed March 2, 1929. Serial No. 343,861.

The invention relates to looms, more par. ticularly to those of the so-called castle type in which the warp threads aretaken from a series of bobbins located usually at b the back of the loom frame, thenled over rollers to form a loop to which is attached a weight for suitably tensioning the threads the bobbins meanwhile being held stationary. A s thread is. constantly being consumed in the weaving, this weight is gradually drawn upwardly until it becomes necessary to release or let-oif further lengths from the respective bobbins. 2 This is generally accomplished manually by drawing outwardly a bobbin on its spindle to unclutch the same therefrom so that it may rotate vfreely on said spindle, the degree. of rotation being checked by the operator holding said bobbin with his hand; Some skill is requiredin this operation and, of course, considerable loss of time is involved when many bobbins must be let-off also,.the threadsfrequently become soiled as a result of the handling. 'Moreover, it occasionally happens that an operator fails to notice that a weight has risen too far so that a smash occurs which entails considerable loss of time and expense in restoring operative conditions.

The present invention has for its object to render the feed of these warp threads auto matic and in a novel manner, the expedients heretofore proposed having proved unsatisfactory. A further object of the invention is to secure substantially constant ten sion on the warp threads and to provide means for accommodating decrease in diameter of the supply bobbins as the thread is taken therefrom.

A still further object resides in the provision of mechanism which involves no handling of the threads, after the bobbins have once been installed, until the supply of such thread becomes exhausted.

Another object is the production of a better weave, which is not now possible with present devices; also, to effect a daily saving in time.

In carrying out the invention, movement, for example of the batten of the loom, is utilized to drive positively, as in effecting an intermittent rotation of, a series of gear wheels which run upon the spindles over which are mounted the bobbins from which the threads are fed, the amount fed being substantially equal to the amount woven by the loom and controlled by the motion of its batten. The actuating mechanism for the gear wheels is so designed, moreover, that the rate of feed may be accelerated as the diameter of the thread supply on the bobbins decreases as it is consumed in the weaving; and this arrangement admits, also, of letting off thread to accommodate any irregularity of feed. i

The nature of the invention, however, will best be understood when described in connection with the accompanying drawings, in which:

Fig. l is a fragmentary side elevation of a castle loom frame with the novel feed mechanism installed.

.Fig. 2 is a fragmentary rear view of the feed mechanism with bobbins removed.

Fig. 3 is a fragmentary side elevation and part vertical section of a number of bobbin spindles and drive mechanism therefor.

Referring to the drawings, 10 designates a portion of the supporting frame or standard of a loom of the so-called castle type and of which the batten portion is repre-. sented at 11, the same comprising two parallel oscillating arm members 12 for swinging the batten. Thearm of said pair nearer the frame 10 is slotted to receive one end of a link 13, the same being'adjustably secured therein as by means of a bolt or pin 14 .passing through the slot and a wing nut 15 ad justable thereon. I

The opposite end of said link is similarly connected, as by means of a bolt or pin 16 and wing nut 17, to the longitudinally slotted arm 18 of a pawl member carrying the pawl 19. Link, 13, moreover, may be adjusted. longitudinally. between these two points of attachment as by means of the respective set screws 20 and 21, the respective ends of the rod fitting through the carrying blocks 22and 23. p

The pawl 19 engages the teeth of a ratchet wheel 25 keyed to a shaft 26 mounted in a l l l l suitable bracket 27 or the like and extending rearwardly from the frame 10. Shaft 26, furthermore, is provided with a worm 28 which, in turn, engages the lowermost bobbin-carrying gear 29 of a train of gears mounted on the vertically disposed bracket 30 secured also to the frame 10 at the back. In addition to the gear wheel 29, the train includes further bobbin-carrying gears 31, 32 and 33 with intermediate or idler gears 34, 35 and 36, the latter being provided to transmit the rotation to the bobbin-carrying gears in manner so that the same shall all rotate in the same direction. The bobbincarrying gears are mounted for rotation upon corresponding spindles 37 38, 39 and 40 which project rearwardly at right angles to the bracket or supporting bar 30 and over which are mounted the bobbins 41, 42, 43 and 44 carrying the thread to be consumed in the operation of weaving.

As shown, a thread 45 is indicated as passing over rollers 46 at the upper portion of frame 10 with loop 47 formed therein and supporting a weighted roller 48 which affords the desired tension on said thread as the same is utilized in the remainder of the loom in manner well understood.

It will be appreciated that as thread is consumed in the weaving, the roller 48 will in the common manner of operation gradually be drawn upwardly; but, in accordance with the present invention, provision is made, as through the operation of the pawl and ratchet device hereinbefore described,

for feeding threads from the various bobbins in amount sutiicient to substantially compensate for the amount utilized in the weaving and which is a function of the movement of batten 11, which movement, in turn, is communicated through the rod 13 to the said pawl and ratchet mechanism. This obviates the usual operation of manual let-off of the threads from the various bobbins in order to restore the roller 48 to its lower position, the feeding of the thread being substantially automatic until it is necessary to replenish the supply. If it be found that, due to change in diameter of the thread stock on a bobbin, the consumption in the loom is more rapid than the supply fed from said bobbin, this automatic feed action can be accelerated by an adjustment of the rod 13 to give greater throw to the pawl 19. \Vhen the bobbin stock then becomes exhausted, a bobbin may readily be removed from its spindle by unclutching or disengaging the same from the perforations 50 in the face of the corresponding gear. The feed of the various bobbins may also be different by providing correspondingly sized gear wheels, asindicated.

A convenient manner, also, of securing the aforesaid bobbin-carrying gears on their respective spindles is by means of washers 51 mounted over the idler wheels and overlapping slightly the teeth of the said bobbincarrying wheels, while the washers in turn are prevented from rising on their spindles by means of cotter pins 52 passing through the same.

By thus maintaining a substantially constant tension on the various threads at all times and feeding forward only substantially as much thread as is required in the weaving operation, a much better and more uniform weave is obtained than is possible with the present system of weaving which must he quently be interrupted to leto1f the threads; and as practically no manual handling of the thread is necessary, after the bobbins have been installed, the threads are less likely to become soiled or damaged; also, very little skill is required for this particular portion of the weaving operation.

I claim:

1. The combination with a loom having an oscillating batten and spindles for retaining bobbins; of an automatic let-oif device for the respective threads of said bobbins, comprising gears rotatably mounted on the respective bobbin spindles adapted to receive and carry the bobbins, and means for positively and intermittently rotating the bobbin-carrying gears, gears for different spindles being of different diameters to afford differing rates of feed from the various bobbins.

2. The combination with a loom having an oscillating batten and spindles for retaining bobbins; of an automatic let-off device for the respective threads of said bobbins,'co1nprising a train of intermeshing gear wheels including idler gear wheels secured against axial movement and gear wheels rotatably and loosely mounted on the respective bobbin spindles to rotate the respective bobbins thereon, means associated with the idler gear wheels to overlap partly the adj accnt bobbincarrying gear wheels, and means actuated from the batten movement for rotating the said train.

In testimony whereof I aflix my signature.

CHARLES HAKEMEYER. 

